Door and control system therefor



Dec. 21, 1965 R. D. HOUK DOOR AND CONTROL SYSTEM THEREFOR 4 Sheets-Sheet 1 Filed April 30, 1962 INVENTQR. Redraw? P. Ho k ATTORNEYS Dec. 21, 1965 R. D. HOUK DOOR AND CONTROL SYSTEM THEREFOR 4 Sheets-Sheet 2 Filed April 30, 1962 INVENTOR ra'ckdrcf BY A TORNEYS Dec. 21, 1965 R. D. HOUK DOOR AND CONTROL SYSTEM THEREFOR 4 Sheets-Sheet 5 Filed April 30, 1962 wk 1M T u NOW W EH

w s I u M a M m a m Dec. 21, 1965 R. D. HOUK DOOR AND CONTROL SYSTEM THEREFOR 4 Sheets-Sheet 4 Filed April 50, 1962 INVENTOR. R 4 .D. How/Y BY 4/ ATTORNEYS 3,224,493 Patented Dec. 21, 1965 United States Patent Ofifice 3,224,493 DOOR AND CONTROL SYSTEM-THEREFOR Richard D. Honk, Alliance, Ohio, assignor to Consolidated Electronics Industries Corporation, a corporation of Delaware Filed Apr. 30, 1962, Ser. No. 190,877 12 Claims. (Cl. 160-189) The invention relates in general to doors having control systems and more particularly, to an upward acting door such as a garage door with a motor connected to move the door in an upward direction, plus a control system to control the actuation of the motor and thus control the operation of the door.

Doors such as garage doors have been devisedwith upward opening movements and where these doors are moved by an electric motor or other power means, suitable controls for the power means are desirable. In upward acting garage doors it is necessary to at least start and stop the motor, with starting being under control of a person and the stopping at least being-effected when the door reaches the fully open or the fully closed position. Many garage door operators have not had satisfactory safety controls to control the movement of the door should the door meet an obstruction to movement and various other control systems have failed to provide a safe operation for doors.

Accordingly, an object of the present invention is to provide a safe door control system.

Another object of the invention is to provide a door and control system therefor inwhich a simple and reliable control circuit is achieved constantly under con trol by a person.

Another object of the present invention is to provide an upward acting door with a door control system wherein the door may be stopped by any of three different means in the downward closing direction.

Another object of the invention is to provide two ditlerent limit switches actuable by linkage of an upward acting door with one limit switch overriding the control effected by the second limit switch.

Another object of the invention is to provide an upward acting door with a control system controlled by movement of a latch latching the door.

Another object of the invention is to provide an upward acting door with a control system wherein three limit switches are used, two actuated by a latch mechanism and a third limit switch capable of overriding the control of the second limit switch.

Another object of the invention is to provide a control system for a door moved by a flexible cable with control effected by the position of a cable sheave guard on a sheave around which the cable passes.

Another object of the invention is to provide a'door control system with a limit switch controlled by position of a latch and capable of being overridden by a second limit switch controlled by position of the door. 1 Another object of the invention is to provide a control system for a door pulled. open by a flexible cable wherein the control system is sensitive to tension on the cable.

vOther objects and a fuller understanding of the invention may be had by referring to the following description and claims, taken in conjunction with the accompanying drawings, in which: FIGURE 1 is an inside elevational view embodying the invention;

FIGURE 2 is an enlarged sectional view on line 22 of FIGURE 1;

FIGURE 3 is a perspective view of the motor and operator in the upper right corner of FIGURE 1;

of a door FIGURE 4 is a perspective view" of the cable sheave in the lower right corner of FIGURE 1;

lever and limit switches.

The invention relates generally to a door '10 which in this embodiment has been illustrated as a garage door. The door 10 is used in connection with a door frame having a header 12, a 'lower wall or floor 13, and side jamb members 14 and 15. The door 10 includes generally an upper panel 16 and a lower panel 17. The upper panel 16 is swingably mounted relative to the door frame as by a first hinge means 21. Second hinge means 22 hinges together the upper and lower panels 16 and 17. The first hinge means 21 hinges the upper'part of the upper panel 16 to the header 12 and the second hinge means 22 hinges the upper part of the lower panel to the lower part of the upper panel 16. The second hinge means 22 includes side hinges 23 and where the door is wide, one or more intermediate hinges 24. Door stops 25 and 26 are mounted on the side jambs 14 and 15, respectively, and maintain the door panels 16 and 17in a slightly outwardly bent position to break the toggle eflectively established by the first and second hinge means'21 and 22 and the upperand lower panels 16 and 17. First and second jamb brackets 27 and 28, respectively, are mounted at the top of the respective side jambs 14 and 15 up against the bottom of the header 12. The jamb brackets carry first and second control arms 29 and 30, respectively. First and second pivot means 31 and 32, respectively, are used on each control arm. The first pivot means 31 pivotally connects one end of each control arm to the respective jamb bracket. The second pivot means 32 pivotally connects the other end of the respective control arm to the door 10. As shown, this second pivot means 32 is connected to the lower panel 17. The second pivot means 32 of the control arms are connected at the side hinges 23 on a lower extension 33 thereof to positively position the distance between the second pivot means 32 and the second hinge means 22. The jamb brackets are mounted directly against the underside of the header 12 and this positively positions the first pivot means 31 relative to the first hinge means 21, thus the first hinge means 21 and the first pivot means 31, plus the control arms 29' and 30 constitute support and control means for movement of the door 10.

The jamb brackets 27"and 28 support. a torque tube or rotatable member 36for rotation on an axis generally parallel to the first hingemeans v21. A bearing 37 sup-I ports one end of the torque tube 36 and a motor actuator 38 supports the other end. The, bearing 37 and motor actuator 38 are interchangeable on jambb'rackets 27 and 28. Motor actuator 38 includes an electric motor 39 driving a=worm 40 and a worm wheel 41. The worm wheel drives through a friction clutch 42 to the torque tube 36. The worm 40 and worm wheel 41 provide irreversible power direction means froni the motor to the torque tube'36.

Depending upon the width of the door 10, one or more cable drums may be used. The door, illustrated uses two: such cable drums 45 and 46. Each cable drum maybe fixed to the torque tube 36 and has spiral grooves 47 therein to receive a flexible cable. Flexible cables 49'an'd 50 areprovided for the respective drums 45 and 46. I The motor 39 is thus capable of rotating the torque tube 36 to wind the cables 49 and 50 on the respective cable drums to exert a lifting force to open the door 10.

First and second cam lock levers or latch levers 51 and 52 are providedon each'si'de of the door 10. These latch levers are movable links connected to the door and are positioned near the second hinge means 22 and are shown as being on the lower panel 17. The levers 51 and 52 are right and left hand but otherwise are identical. FIGURE illustrates the latch lever 52 and it will be understood that the latch lever 51 has a reversedconstruction. The

latch lever 52 is pivoted on a pivot axis 53 fixed relative to the lower panel 17. The lever 52 has an actuator end 54 and a cam lock portion 55 which is skewed or has about a one inch lead of a leading edge 56 relative to a trailing edge 57 thereof. This cam lock portion 55 cooperates with a latch plate 58 fixed on the side jamb '15. The approximately one inch lead of the leading edge 56 provides a camming action to positively bring the door closed against the door stops 25 and 26. v A return spring 61 is a tension spring having one end fixed to the lower panel 17 and the other end fixed at a point 63 on the latch lever 52. This return spring urges the latch lever 52 to a first limit position relative tothe door panel 17 as established by -a stop 64. This stop 64 may be provided by a bolt or lag screw fastening a plate 65 to the lower panel 17. This plate 65 is an extension of the side hinge 23 and also mounts the pivot 53 for the latch lever 52.

A cable sheave 68 is journalled on an axle 69 carried in a bracket 70 fixed near the bottom of the lower panel 17 A cable sheave guard 71 is also pivoted on the axle 69 and has an opening 72 through which the respective cable passes. Each flexible cable has first and second runs 73 and 74, respectively, and the first run of cable 73 extends downwardly from the respective cable drum through the cable sheave guard 71 and around the respective sheave 68. The second .run of cable 74 extends upwardly from the respective sheave 68 to the respective latch .lever 51 or 52. This second run of cable is fixed to the latch lever in a convenient manner as by wrapping around the pivot 63 and being fixed by a cable clamp 75. A second limit position is provided for the latch lever 52 and this is with the latch lever moved through an arc of about 100 degrees by pull on the cable which pulls downwardly on the second run 74 against the urge of the return spring 61. "This second limit position of tthe lever 52 is thus determined by alignment of the pivot 53, the pivot 63 and the second run 74 going to the sheave 68. The cam lock portion 55 is positioned so that the first portion of about 30 or 40 degrees of the approximately 100 degree are of movement of the lever 52 is that which unlocks or unlatches the door and then as the cables are wound on the cable .drumsand become taut, the latch levers 51 and 52 swing to their downward or second limit position and then a lifting force is exerted on the lower panel. This lifting force .is exerted essential y at the lower edge of this lower panel 17 and the control arms together with the first hinge means 21 and the first pivot means 31 establish controlled quadrilateral movement of the door panels 16 and 17. During this door opening movement, the upper panel .16 swings upwardly and out wardly to a generally horizontal position and the lower panel 17 swings approximately .180 degrees relative to the upper panel 16 to fold and collapse upwardly substantially against the upper panel 16.

First, second and third limit switches 81, 82 and 83 are provided in a control circuit 84. The first limit switch 81 is a leaf spring insulatively mounted on the lower panel 17 outboard of the side hinge 23. The outer tip 85 of this leaf spring blade is adapted to be contacted by the inner .face of the cam lock portion 55 of the latch lever 52. This first limit switch 81 is closed in the first limit position shown in full lines in FIGURE 5. The control circuit 84 is a grounded or single conductor system and, hence, the electrical contact is made between the leaf spring blade 81 and the cam lock portion 55 which is grounded through the plate 65 and control arm 30 and jam'b bracket 28 to the case of the motor actuator 38.

The second limit switch 82 has another leaf spring blade insulatedly mounted on the lower panel 17. This blade has an outer end 86 which is adapted to be engaged by the under face of the latch lever 52 as it swings near the second limit position. This second limit switch is also a normally open switch and is actuated closed by contact with the latch lever 52 in a range of about 10 to about 40 degrees spaced from the second limit position of the latch lever 52.

The third limit switch 83 is insulatedly mounted on the bracket 70 of the cable sheave 68. This third limit switch 83 has a spring blade 86 carrying an insulated projection 87 adapted for actuation by movement of the cable sheave guard 71. The third limit switch 83 also includes a second leaf spring 88 carrying a contact 89 adapted to be electrically closed relative to the spring blade 86 when the cable sheave guard 71 actuates the projection 87. In the position of the cable sheave guard 71, shown in FIGURE 4, the third limit switch 83 is not actuated closed and is a normally open switch. Upon 'pivotal movement of the cable sheave guard 71, about 5 or 10 degrees in the counter-clockwise direction, however, the third limit switch 83 is actuated closed. This will be with the first and second cable runs 73 and 74 diverging about 5 or 10 degrees. This third limit switch 83 remains closed for all further counter-clockwise movements of the cable sheave guard 71.

The control circuit 84 is energized from a suitable voltage source such as an alternating voltage source 93. A control transformer 94 is energized through an overload protector .95. The electric motor 39 is also energized through this overload protector '95 and has first and second windings 96 and 97, respectively. This motor is a reversible capacitor induction motor having a capacitor 98. The motor 39 has a rotor 99 which drives through the friction clutch 42 to a centrifugal mechanism 100. A torque switch 101 is driven from the centrifugal mechanism to be opened upon acceleration of the "motor to about one-half speed.

The control circuit 84 also includes a ratchet relay 104 having a relay coil 105 energizable from a secondary 106 of the control transformer 94. One end of the secondary 106 is grounded for a grounded or single conductor control system and the other end of the relay coil 105 is connected to a terminal 109 on a terminal board 107. A push button switch 108 is connected across the terminals of the terminal board 107 to ground 90 to establish energization of the relay coil 105. This push button switch may be a manual switch such as an ordinary door bell push button operating on the low voltage secondary 106, for example 24 volts. Also, this push button switch 108 may be representative of a radio controlled switch closed by actuation of a radio transmitter in an automobile for remote operation of the door 10.

A relay armature position switch 110 is a normally Closed switch connected to be actuated to the open position by energization of the relay coil 105 and, hence, actuation of the relay armature. The relay armature 111 actuates a ratchet 112 to rotate a plurality of cams 113 and, accordingly, actuate a series of relay contacts 114 to .117, inclusive, in .a predetermined sequence. The relay contacts 114'to 117 are normally open contacts and are shown in the open position in FIGURE 6 which corresponds to the door closed position of the door 10. Conductor 118 of the voltage source 93 is connected to each of the contacts 114 to 116. Conductor 119 of the voltage source 93 is connected through a lamp 120 to the contacts 116. This lamp 120 may be mounted on the motor actuator 38 to illuminate the interior of the garage or other structure for which the door"1'0 is a closure. A conductor 121 connects motor winding 97 to the other side of contacts 114 and the conductor 122connects the motor winding 96 to the other side of relay contacts 115.

The relay contacts 114-1'16 are power contacts to control energization to the motor 39 and lamp 120 and relay contacts 117 are control contacts forming 'part of a control circuit 123. A conductor 124 is connected from the relay armature position switch 110 through the relay con tacts 117 to a terminal 125. The torque switch 101 is connected between terminal 125 and ground. A conductor 126 leads from terminal 125 to a junction 127 from which a conductor 128 leads to the first limit switch 81. Another conductor 129 leads from the junction 127 to the third limit switch 83 actuated by the cable sheave guard 71. A conductor 130 is connected from the other side of this third limit switch 83 to the second limit switch 82. The other side of the second limit switch 82 is connected to ground 90.

As viewed in FIGURES 5 and 7, the latch lever 52 has a first limit position 131 as shown in solid lines in FIGURES 5 and 7 and has a second limit position 132 as shown in dotted lines in FIGURES 5 and 7. The first limit position 131 of this latch lever 52 is caused by the urging of the return spring 61 urging this latch lever 52 against the stop 64. As stated above, the first limit switch 81 is closed with the latch lever 52 at the first limit position 131. This first limit switch 81 is actuated to a closed position by grounding the leaf blade of this switch against the cam lock portion 55 of the latch lever and this grounding occurs generally through an arc 133. The are 133 is a range of actuation of this first limit switch 81 as established by the radial lines 131 and 135. The radial line 135 is in the order of 40 to 50 degrees from this first limit position 131.

The second limit switch 82 is also actuated to a closed position by being grounded against the latch lever 52. The leaf blade 86 contacts the underside of this latch lever 52 through an are 138. This arc is defined by radial lines 139 and 140 with the first radial line 139 about 5-10 degrees from the second limit position 132 of the latch lever 52. The second radial line 140 is about 20 to 30 degrees from the second limit position 132.

The third limit switch 83 is a normally open switch and is open in the position shown in FIGURES 4 and 7. This switch in FIGURE 7 is shown distorted to a three dimensional View for clarity of action. In FIGURES 2 and 4, it will be noted that the first and second cable runs 73 and 74 are substantially parallel with both substantially vertical. This is the position of the cable runs 73 and 74 with the door closed. This may be considered a first limit position established by the radial line 141 on FIG- URE 7. The phantom position 103 in FIGURE 2 showing the door in full open position shows the position of the cable sheave 68 and it will be noted that the first cable run 73 which extends from the cable drum 36 to the sheave 68 will, at that time, be making an obtuse angle of about 160 degrees relative to the second cable run 74. Thus, the first cable run 73 swings through an angle of about 160 degrees relative to the second cable run 74 during the door opening movement. Also and necessarily, the cable sheave guard 71 swings through this approximately 160 degree angle. On FIGURE 7, a radial line line 142 illustrates the position at which the third limit switch 83 will be actuated closed and this third limit switch 83 remains closed throughout the remainder of the approximately 160 degree movement in a counterclockwise direction as viewed in FIGURE 7.

Operation As best shown in FIGURE 2, the door 10 is constructed to swing upwardly and outwardly in the door opening movement. The upper panel 16 swings from a generally vertical to a generally horizontal position and the lower panel 17 also moves from a generally vertical to a generally horizontal position but the second hinge means 22 and control arms 29 and 30 established that the lower panel 17 moves approximately 180 degrees relative to the upper panel 16. The door 10 is supported substantially entirely in the closed position by the first hinge means 21 and the first pivot means 31. These two points of support plus the control arms 29 and 30 provide support and control means for the door '10 and support a 6 majority of the weight throughout the entire door opening and door closing movement. Thus, it has been found that a 385 lb. door required only 110 lbs. total pull on the cables 49 and 50 throughout the entire opening movement. Thus, the door 10 requires no counterbalancing means because the motor 39 may easily supply the necessary power to open the door 10 in a normal time of IO-15 seconds. The motor 39 drives the torque tube 36 to wind the cables 49 and 50 on the respective cable drums, thus exerting a generally vertical lifting force on the bottom of the lower panel 17 and this moves the door through the intermediate position 10A to the open position 10B shown in phantom in FIGURE 2.

The electrical control circuit 84 controls the door opening and closing movement. When the push button switch 108 is depressed or the radio control switch is actuated across the same terminal board 107, the relay coil 105 will be energized. FIGURE 6 shows the control circuit 84 in the de-energized position corresponding to the door closed position. Energization of relay coil 105 moves armature 111 to move the ratchet 112 and the cams 113 to the first of four sequential positions. This first position corresponds to a door opening condition and closes contacts 114, 116 and 117. Contacts 116 energize the lamp 120 to illuminate the inside of the garage. Contac-ts 114 are closed to energize motor winding 97 directly and energize motor winding 96 through the capacitor 98 to rot-ate the rotor 99 in one direction for a door opening movement. The motor 39 drives through the worm 40 and worm wheel 41 to the friction clutch 42 and the torque tube 36. During initial acceleration of the rotor 99, the torque switch 101 is opened and latch lever 52 is partially rotated to open limit switch 81. Accordingly, the torque tube 36 is rotated in a direction towind the cables on the cable drums and thus exert a lifting force on the door panels 16 and 17.

The initial movement of the cables pulls upwardly on the first cable run 73 and downwardly on the second cable runs 74. This swings the latch lever 52 counterclockwise as viewed in FIGURES 5 and 7. This latch lever 52 has a total of about degrees arcuate movement between the first and second limit position 131 and 132 and about the first 30 degrees of movement unlatches the cam lock portion 55 from the latch plate 58. After about the first 40 or 50 degrees of movement of the latch lever 52, the first limit switch 81 is opened.

This occurs quickly after energization of the motor 39, and thereafter push button switch 108 may be released to de-energize the relay coil without other change in the circuit condition. As the latch lever 52 swings about 70 or 80 degrees to the radial line 140, the second limit switch 82 will be actuated but this does not change the circuit condition because the third limit switch 83 is still open at this time. When the latch lever 52 has swung about another 20 degrees to the radial line .139, the second limit switch 82 will again become open. As the latch lever 52 reaches the second limit position 132, the cables are placed under increased tension and begin to lift the door 10. The return springs 61 may have a force of about 15 lbs. for example, but it has been found that only a slight excess of force, for exampie 20 lbs. force, is necessary on the cables 49 and 50 to commence the door opening movement. At this time, the cam lock portions 55 are fully disengaged from the latch plates 58 so that the door opens gradually without any sudden jumping movement away from the door stops 25 and 26. As the door starts its opening movement, the cable runs 73 and 74 diverge to a point of divergence of about 5 or 10 degrees, at which point the second radial line .142 is reached to actuate closed the third limit switch '83. This does not change the circuit condition, however, because the second limit switch 82 is open at this time. The door continues in its opening movement through an intermediate position 10A to the full open position 10B shown in phantom in FIGURE 2. It is in the intermediate position 10A at which the maximum lifting force must be applied to the cables 49 and 50 and this ordinary household motor such as A may easily raise the.door 10' without aid from any counterbalance means.

As the door' approaches the fullopen position 1013, the load on the cables is-again reduced to only about 20- 25.lbs. force for. a door in the order of 400 lbs.. This is because the control arms 29 and 30 in elfect act as a triangular braceto support the door 10 in the open position and because the second pivot means 32 is approaching a high enough position relative to the first and second hinge means 21- and'22 to almost lockthe door in the up position. Ifl the second pivot means 32is made to lie above the line joining the first andsecond hinge means 21 and 22, thenit is found that the door 10 will lock up in the full open position 10B. It is not desired to achieve this locking up condition in this motorized door because it is desired to have the door 10 close by gravity rather than being driven closed by the motor 3 9.

When thedoor 10 reaches the full open position, the lower panel .17 is collapsed up against the upper panel 16 with the control arms 29 and 30 sandwiched thenebetween and, thus, the lower panel 17 can go no higher. Accordingly, the torque tube 36 is stalled and the friction clutch 42 slips to deactuate the centrifugal mechanism 100 and closethe torque switch 101. This pulses or energizesthe relay coil 105 through the then closed relay contacts 110 and 117.. The relay 104-is ratchetedto thethird position whichis a-door open position. In this door open position, only the relay contacts 116 remain closed to keep the lamp 120 illuminated.

In the door open position, the motor 39 is of course de-energized with a small amount of weight from the door 10 acting through the cable runs 73 to apply a small torque to the torque'tube 36. T his-torque is resisted by the worn-140 and worm wheel 41 since this is a form of irreversible power direction means preventing transmission of power from the torque tube 36 to the motor39.

Thus, this irreversible power direction means acts as a braketo hold the door in' the open position 103;

The door closing movement is initiated by depressing the pushbutton switch 108 o-r'its counterpart radio control switch, not shown. This actuates the relay coil 105 to ratchet the cams 1 13 to thefourth' position which is a" door closing'condition. This fourth position closesc-ontacts 1 15, '1 16 and 117 with contacts 116 again keeping thelamp 120 illuminated. Closing of the contacts 115 energizes the motor winding 96 directly and motor winding '97 through the capacitor 98 for reverse' rotation of the'rotor9 9. This is a door closing direction and thus the torque tube-36 is driven inthe reverse direction. ThlS doesnot push 'the door closed but does pay out the cables not change the circuit operation since the secondlimit switch 82 is then also open. As the door is fully closed, the motor continues to payout the flexible cables and,

thus, the return springs 61'urge the latch levers 52 from the sec-nd limit position 132 toward the-first limit position 131. During the arc of movement 138, the second limit switch 82 will be'actuated, but this does notchang'e the circuit condition because the third limit switch 83 is then open. At the radial line 135', the first limit switch 81' is actuated closed and this does energize the relaycoil 105 through the then closed relay contacts '117 and 1 The relay 104 is thus ratchete'd to retur-n-to the is about 30-35 of the total weight ofthe door 10 This. light load means that an.

first position which is the door closed condition. In this position, all contacts 114-117 are open and, hence, the motor 39 is de-energized. The coasting of the motor rotor 9-9 is suificient to permit the latch lever 52- to swing to the first limit position 131 where the cam lock portion 55 latches or locks the door. Thus, the door is locked at the two sides near the second hinge means 22 to prevent unauthorized entry into thegarage. It will be noted that the exterior. of the door 10 presents a smooth appearance with no external handles and, thus, nothing may be grasped to aid forcible entry into thegarage.

The above description shows that the torque switch 101 is that-which stops the motor in the full open position and the first limit switch 81 is that which stops the motor in the full closed position. The control circuit 84 also provides important safety features. One of these safety features is that at any'point in the upward or downward closing movements of the door, the door may be stopped if a person notice-s that it needs to be stopped for any reason. This may be accomplished by simply depressing the push button switch 108 or the radio control switch,

not shown, in parallel therewith. This push button switch 108 will actuate the relay coil to index the relay 104 second limit switch 82-is much more sensitive'to obstruction of downward movement of the door. Upon meeting any such obstruction, the cables are still being payed out and this quickly releasesthe tension on the cables; The return spring'61 thus quickly swings the latch lever 52 clockwise and about 5or IO'degrees movement to the radial line 139*is all that is needed to actuate the second limit switch 82. It will be noted'that in the intermediate position 10A, the cable sheave guard 71 is in such a position to-close the third limit switch 83, thus-closing of the second limit switch 82- at this time will index the The' relay 104- to a motor and door stopped condition. irreversible power direction means of worm 40 and worm wheel 41 thus stops the door when the motor 39 is stopped.

The first limit switch 81 is a switch sensitive to cable tension to shut off the motor 39. The second limit switch 82 however is a switch sensitive to a greater cable tension and thus a smaller percentage change of tension from that established in the door closing movement, and thus is a safety switch. The third limit switch 83 is a switch sensitive to the door position, especially position of the lower panel 17. This third limit switch 83 disables control of the relay 104-by the second limit switch 82 whenever the door ispracticallyclosed but permits the second limit switch 82 to be in control of the control circuit 84 throughout theentire intermediate range of downwardmovement of the door 10. When the third limit switch 83 is actuated to an open position in the last small distance or minor distanceof door closing, this disables the second limit switch 82 so that the latch lever 52 must swingthrough approximately 50 degrees to the radial line before the motor 39 is de-en'ergized. This permits the small coasting of the motor andtorque tube 36 to complete the closing movement of the latch lever 52 to the 'fully latched position. Thus, this assures that the door will be closed and locked at the end of the door closing movement.

Although this invention has been described in its preferred form with a certain degree of particularity, it is understood that the present disclosure of'the preferred form has been made" only by way of -example and that 9 numerous changes in the details of construction and the combination and arrangement of parts may be resorted to without departing from the spirit and the scope of the invention as hereinafter claimed.

What is claimed is: 1. A door for a door frame, comprising, in combination, at least one door panel,

means to mount said panel for upward opening movement, drive means including an electric motor connected to pull on a movable link, means connecting said movable link to said panel, urging means urging said link toward a first limit position, said drive means connected to said link to pull same through a path of movement against the urging of said urging means from said first to a second limit position and said drive means exerting an upward opening force on said door at said second limit position, limit switch means connected to be actuated from a first to a second condition in accordance with movement of said door panel to a position within a minor distance of being closed on the door frame, electrical circuit means controlling energization to said electric motor and including a second switch, said circuit means including said limit switch means to disable control of :said motor by said second switch until said limit switch means has been actuated to said second condition. 2. A door for a door frame, comprising, in combination, at least one door panel,

means to mount said panel for upward opening movement, drive means including an electric motor connected to pull on a movable link via a flexible cable, means connecting said movable link to said panel, urging means urging said link toward a first limit position, said drive means connected to said link to pull same through a path of movement against the urging of said urging means from said first to a second limit position and said drive means exerting an upward opening force on said door at said second limit position, limit switch means connected for actuation in accordance with movement of said link and actuated from a first to a second condition in response to change in tension on said cable, electrical circuit means controlling energization to said electric motor, and said circuit means including said limit switch means connected to de-energize said motor upon actuation of said limit switch means. 3. A door for a door frame, comprising, in combination, at least one door panel,

means to mount said panel for upward opening movement, drive means including an electric motor connected to pull on a movable link via a flexible cable, means connecting said movable link to said panel, urging means connected to urge said link toward a first limit position, said drive means connected to said link to pull same through a path of movement against the urging of said urging means from said first to a second limit position and said drive means exerting an upward opening force on said door at said second limit position, first limit switch means connected for actuation in accordance with movement of said link and actuated from a first to a second condition in response to change in tension on said cable, second limit switch means connected to be actuated from a first to a second condition in accordance with tion, at least one door panel,

means to mount said panel for upward opening movement,

a movable link connected to said panel and having first and second limit positions,

drive means including an electric motor connected to pull on said movable link via a flexible cable,

urging means connected to urge said link toward said first limit position,

said drive means connected to said link to pull same through a path of movement against the urging of said urging means from said first to said second limit position and said drive means exerting an upward opening force on said door at said second limit position,

first limit switch means connected for actuation in accordance with movement of said link and actuated from a first to a second condition in response to change in tension on said cable,

second limit switch means connected to be actuated in accordance with movement of said link and actuated from a first to a second condition by a second and greater amount of tension on said cable,

third limit switch means connected to be actuated from a first to a second condition in accordance with movement of said door panel to a position within a minor distance of being closed on the door frame,

electrical circuit means including a relay controlling energization to said electric motor,

said circuit means including said first limit switch means connected to dc-energize said motor upon actuation of said first limit switch means,

means connecting said second limit switch means in i said circuit means to stop downward movement of said door upon actuation of said second limit switch means,

and means connecting said third limit switch means in said circuit means to disable actuation of said relay by said second switch means until said third limit switch means has 'been actuated.

' 5. A door for a door frame, comprising, in combination, at least one door panel,

means to mount said panel for upward opening movement,

drive means including an electric motor and a movable link connected to said panel,

means urging said link toward a first limit position relative to the door,

said drive means connected to said link to pull same through a path of movement against the urging of said urging means from said first to a second limit position and said drive means exerting an upward opening force on said door at said second limit position,

limit switch means connected to be actuated from a first to a second condition by movement of said link within a minor portion of said path from said second limit position,

electrical circuit means controlling energization to said electric motor,

and said circuit means including said limit switch means acting as safety switch means to stop downward movement of said door during the intermediate range l l of downward door movement whenever door movement is obstructed to move said link to actuate said limit switch means to said second condition. 6. A door for a door frame, comprising, in combination, at least one door panel,

mean-s to mount said' panel for upward opening movement, drive means including an electric motor and a movable link connected to said panel, means urging said link toward a first limit position relative to the door,

said drive means connected to said link'to pull same through a path of movement against the urging of said urging means from said first to a second limit position and said-drive means exerting an upward opening force on said door at said second limit position,

first limit switch means connected to be actuated from a first to a second condition by movement of said link within a minor portion of said path from said second limit position,

electrical circuit means controlling energization'to said electric motor,

said circuit means including said first limit switch means' acting as safety switch means to stop downward movement of said door'during the intermediate range of downward door movement whenever door movement is obstructed to move said link to actuate said first limit switch means to said second condition,

second limit switch means connected to be actuated from a first to a second condition by movement of said door panel to a position within a minor distance of being closed on the door frame,

and means connecting said second limit switch means in said circuit means to disable control of said motor by said first switch means until said door panel has moved to a position actuating said second limit switch means to said second condition.

7. A door for a door frame, comprising, in combination, at least one door panel,

means to mount said panel for upward opening movement,

drive means including an'electric motor and a movable link connected to said panel,

means urging said link toward a first limit position relative to the door,

said drive means connected to said link to pull same through a ath of movement against the urging of said urging means from said first to a second limit position and said drive means exerting an upward opening force on said door at said second limit position,

v first limit switch means connected to be actuated from a first to a second condition by movement of said link within a first minor portion of said path from said first limit position,

second limit switch means connected to be actuated from a first to a second condition by movementof said link within a second minor portion of said path from said second limit position, v

electrical circuit means controlling energization to said electric motor,

said circuit means including said first limit switch means to de-energize said motor when said door has closed on the door frame and said urging means has moved said link to actuate said first limit switch means,

means connecting said second limit switch'means in said circuit means acting as safety switch means to stop downward movement of said door during the intermediate range of downward door movement whenever door movement is obstructed to have said urging means move said link to actuate said second limit switch means,

12 third limit switch means connected to be actuated from a first to a second condition by movement of said door panel to a position within a minor distance of being closed on the door frame,

and means connecting said third limit switch means in said circuit means to disable control of said motor by said second switch meansuntil said door panel has moved to a position actuating said third limit switch means.

8. A door for a door frame, comprising, in combination, at least one door panel,

-means to mount said panel for upward opening movement,

a movable latch connected to said panel,

means urging said latch toward a latched first limit position relative to the door'frame,

drive means including an electricmotor,

said drive means connected to said latch to pull same through a path of movement against the urging of said urging means from said first to a second limit position with the first portion of movement on said path unlatching said latch from said door frame and said drive means exerting an upward opening force on said door at said second limit position,

limit switch means connected to be actuated from a first to a second condition by movement of said latch within a minor portion of said path from said second limit position,

electrical circuit means including a relay controlling energizationto said electric motor,

and said circuit means including said limit switch means acting as safety switch means to stop'downward movement of said door during the intermediate range of downward door movement whenever the door meets an obstruction to have said urging means move said latch to actuate said limit switch means to said second condition.

9. A door fora door frame, comprising, in combination, at least one door panel,

means to mount said panel for upward opening movement,

amovable latch connected to said panel,

means urging said latch toward a latched first limit position relative to the door frame,

drive means-including an electric motor,

said drive means connected to said latch to pull same through a path of movement against the urging of said urging means from" said first to' a Second limit position with the first portion of movement on said path unlatching said latch from said door frame and said drive means exerting an upward opening force on said door at said second limit position,

first limit switch means connected to be actuated from a first to a second condition by movement of said latch within a minor portion of said path from said second limit position,

electrical circuit means including a relay' controlling energizat-ion to said electric motor,-

said circuit means including said limit switch means acting as safety switch means to stop downward movement of said door during the intermediate range of downward door movement whenever the door -me'et-s an obstruction to have said urging means move said latch to actuate said limit switch means to said second condition,

second limit'switch me'ans connected to be actuated from a first to a second condition by movement of said door panel to a position within a minor distance of being closed on the door frame,

and means connecting said second limit switch means in said circuit means to disable actuation of said relay by said first switch means until said door panel has moved to a positionactuatingsaid second limit switch means to said second condition.

10. A door for a door frame, comprising, in combination, at least one door panel,

means to mount said panel for upward opening movement,

a movable latch connected to said panel,

means urging said latch toward a latched first limit position relative to the door frame,

drive means including an electric motor,

said drive means connected to said latch to pull same through a path of movement against the urging of said urging means from said first to a second limit position with the first portion of movement on said path unlatching said latch from said door frame and said drive means exerting an upward opening force on said door at said second limit position,

limit switch means connected to be actuated from a first to a second condition by movement of said latch within a first minor portion of said path from said first limit position,

electrical circuit means including a relay controlling energization to said electric motor,

and said circuit means including said limit switch means to actuate the relay to de-energize said motor when said door has closed on the door frame and said urging means has moved said latch to actuate said limit switch means to said second condition.

11. A door for a door frame, comprising, in combination, at least one door panel,

means to mount said panel for upward opening movement,

a movable latch connected to said panel,

means urging said latch toward a latched first limit position relative to the door frame,

drive means including an electric motor,

said drive means connected to said latch to pull same through a path of movement against the urging of said urging means from said first to a second limit position with the first portion of movement on said path unlatching said latch from said door frame and said drive means exerting an upward opening force on said door at said second li-mit position,

a first limit switch connected to be actuated from a first to a second condition by movement of said latch to a point within a first minor portion of said path from said first limit position,

a second limit switch connected to be actuated from a first to a second condition by movement of said latch to a point a second minor portion of said path away from said second limit position,

electrical circuit means including a relay controlling energization to said electric motor,

said circuit means including said first limit switch to actuate the relay to de-energize said motor when said door has closed on the door frame and said urging means has moved said latch to actuate said first limit switch to said second condition,

means connecting said second limit switch in said circuit means to stop downward movement of said door during the intermediate range of downward door movement whenever the door meets an obstruction to have said urging means move said latch to actuate said second limit switch to said second condition,

third limit switch means connected to be actuated from a first to second condition by movement of said door panel to a position within a minor distance of being closed on the door frame,

and means connecting said third limit switch means in said circuit means to disable actuation of said relay by said second switch until said door panel has moved to a position actuating said third limit switch means to said second condition.

12. A door for a door frame, comprising, in combination, at least one door panel,

means to mount said panel for upward opening movement,

a latch lever pivoted to said panel,

return spring means urging said latch lever toward a latched first limit position relative to the door frame,

drive means including an electric motor connected to pull on a flexible cable,

said flexible cable connected to said latch lever to pull same through an are against the urging of said return spring means to a second limit position with the first portion of said are unlatching said latch lever from said door frame and exert an upward opening force on said door,

a first limit switch connected to be actuated from a first to a second condition by movement of said latch lever within a first small are from said first limit position,

a second limit switch connected to 'be actuated from a first to a second condition by movement of said latch lever within a second small are from said second limit position,

electrical circuit means including a relay controlling energization to said electric motor,

said circuit means including said first limit switch to actuate the relay to stop said motor when said door has closed and said return spring means has moved said latch lever to within said first small are from said first limit position,

means connecting said second limit switch in said circuit means to stop downward movement of said door during the intermediate range of downward door movement whenever cable tension is released to have said return spring means move said latch lever to within said second small are from said second limit position to actuate said second switch,

third limit switch means connected to be actuated from a first to a second condition by movement of said door panel to a position within a small distance of being closed on the door frame,

and means connecting said third limit switch means in said circuit means to disable said second switch until said door panel has moved to a position within said small distance of being closed on the door frame.

References Cited by the Examiner UNITED STATES PATENTS 1,374,053 4/ 1921 Brawner 292-225 1,412,871 4/1922 Johnson 160-193 X 1,465,088 8/ 1923 Murray 292-225 1,528,705 3/ 1925 Sonner 292-225 2,007,552 7/ 1935 Vetterlein 160-189 X 2,920,151 1/ 1960 Lawich 268-59 2,992,378 7/ 1961 Schneider 318-469 HARRISON R. MOSELEY, Primary Examiner. 

1. A DOOR FOR A DOOR FRAME, COMPRISING, IN COMBINATION, AT LEAST ONE DOOR PANEL, MEANS TO MOUNT SAID PANEL FOR UPWAWRD OPENING MOVEMENT, DRIVE MEANS INCLUDING AN ELECTRIC MOTOR CONNECTED TO PULL ON A MOVABLE LINK, MEANS CONNECTING SAID MOVABLE LINK TO SAID PANEL, URGING MEANS URGING SAID LINK TOWARD A FIRST LIMIT POSITION, SAID DRIVE MEANS CONNECTED TO SAID LINK TO PULL SAME THROUGH A PATH OF MOVEMENT AGAINST THE URGING OF SAID URGING MEANS FROM SAID FIRST TO A SECOND LIMIT POSITION AND SAID DRIVE MEANS EXERTING AN UPWARD OPENING FORCE ON SAID DOOR AT SAID SECOND LIMIT POSITION, LIMIT SWITCH MEANS CONNECTED TO BE ACTUATED FROM A FIRST TO A SECOND CONDITION IN ACCORDANCE WITH MOVEMENT OF SAID DOOR PANEL TO A POSITION WITHIN A MINOR DISTANCE OF BEING CLOSED ON THE DOOR FRAME, ELECTRICAL CIRCUIT MEANS CONTROLLING ENERGIZATION TO SAID ELCTRIC MOTOR AND INCLUDING A SECOND SWITCH, SAID CIRCUIT MEANS INCLUDING SAID LIMIT SWITCH MEANS TO DISABLE CONTROL OF SAID MOTOR BY SAID SECOND SWITCH UNTIL SAID LIMIT SWITCH MEANS HAS BEEN ACTUATED TO SAID SECOND CONDITION. 